Out of the corner of his eye, he saw wide receiver Amari Cooper stop, which immediately triggered to Lee that Prescott was throwing back across the field. As Prescott threw the ball, Lee darted to his right and tipped the pass away for an incompletion.

"I should've picked it off," Lee said.

The play was a sign Lee can still get it done.

It is easy to overlook Lee on the Cowboys' defense these days.

Leighton Vander Esch earned a Pro Bowl appearance as a rookie at weakside linebacker last season. He led the Cowboys in tackles with 176, according to the Cowboys coaches' count. Jaylon Smith finished second with 150 and added four sacks, five tackles for loss, 13 pass deflections and two forced fumbles and fumble recoveries.

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Lee played in only seven games in 2018 because of recurring hamstring injuries. When he returned late in the season, he told the coaches not to mess with Vander Esch and Smith because they were playing so well, which limited his own playing time. Lee's 37 tackles were a career low, coming in just 220 snaps. In 2017, he missed five games because of hamstring injuries, but Lee still had 118 tackles, 13 tackles for loss, four quarterback pressures and an interception.

There was a time when the Cowboys could not win without Lee. From 2015 through 2017, they were 1-7 without him.

Last season, the Cowboys found out they could succeed without him -- as Vander Esch, a rookie first-round pick, and Smith, a second-rounder in 2016, flourished.

However, Dallas wasn't quite ready for life without Lee, and in March, he agreed to a restructured contract that will pay him $3.5 million and give him the chance to earn $7 million based on playing time and a playoff appearance.

Lee could have looked elsewhere without the pay cut, but 10 years with the Cowboys mattered to him.

"I mean, it's gone too fast," said Lee, who was the Cowboys' second-round pick in 2010. "It's been a dream come true. I've been so blessed to be a part of this organization, to play with some incredible football players. I've been lucky to have a lot of faith put in me by the Joneses, stuck with me through a lot of injury and tough times; for me, the ultimate goal is to be able to bring a championship here. By now, I was hoping we would have one, but every time we step in here it's a blessing. It's so much fun. I feel like a rookie half the time I walk in here."

Lee, who will turn 33 a few days before the Cowboys leave in July for the start of training camp in Oxnard, California, will need to learn a new position: strongside linebacker. In the 4-3 scheme, the strongside linebacker can play on the ball or off the ball, depending on the call or formation, but there aren't many snaps. Last season's starter, Damien Wilson, played only 285 snaps with the Cowboys using their nickel defense more.

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When healthy, Lee rarely came off the field. Now, he has to adjust to a new role.

"The situations, some of them are very similar to what I've done in the past where I'm off the ball and able to run, sometimes on the ball; try to pride myself on being versatile, being able to adapt, being able to play different positions and learn them and hopefully become an expert at it," Lee said. "I have a ton of help. I love being out there, and I think I'll improve as I go."

In his first two years in the NFL, Lee was on the other part of this life cycle as a player. He was the up-and-comer as Keith Brooking worked into the twilight of his career. Brooking made five consecutive Pro Bowls in an 11-year run with the Atlanta Falcons before signing with the Cowboys as a free agent in 2009. He was 35 and started every game during Lee's rookie season. In 2011, Lee started 15 games while Brooking started three in the Cowboys' 3-4 scheme.

Lee looked up to Brooking, and he maintains a close relationship with him to this day.

Brooking "had an extreme amount of success, still approached the game with a certain type of intensity day in and day out, and that's something I admire," Lee said. "Even as good as he is, as much success as he's had, he's still acting like he's a rookie when he comes in here, coming in here with so much intensity. So for me, that's the thing.

"Hey, I'm 10 years into this, but I still think I have a lot to provide; I'm still working to get better every day."

Vander Esch and Smith are glad they can lean on Lee, who runs the meeting room. The coaches are glad he is back, too.

#DallasCowboys veteran Sean Lee comments on his adjustment to strong-side linebacker and the importance of building bonds with teammates during the offseason.

"It's the way we get three really good players on the field at once. Really good players," Marinelli said. "And so then he also has the chance at [middle and weakside linebacker] in the rotation situation there, guys get tired. So we'll get his reps, and hopefully we'll keep these guys all healthy."

Cowboys coach Jason Garrett sees another benefit to having Lee.

"Sean is one of those guys who has such great energy and such great leadership," Garrett said. "He's the guy out there in front of the drills, showing everybody how to do it. You see him play Sam linebacker. You see him play some of the other linebacker spots. He's jumping in on special teams. He's just someone who loves to play football. As we get closer into this thing, we'll sort out everybody's role. It wasn't like, 'Hey, this whole acceptance thing.' He's just trying to get better as a football player."

The Cowboys are mindful of Lee's practice work. During the organized team activities and minicamp, he was given the middle day of the three-day sessions off. But with Vander Esch rehabbing a pelvic issue, Lee has seen more work than he had in previous offseasons. During training camp, he likely will follow a similar schedule.

"There is room for me to improve," Lee said. "I think when I'm at my best, I'm as good as I've ever been."